Share Plans (Tables)

6 Months Ended

Jun. 30, 2023

Share-Based Payment Arrangement [Abstract]

Share-based Compensation Expense

Total share-based compensation expense for the three and six months ended June 30, 2023 and 2022 was as follows:

	Three months ended				Six months ended
In millions	June 30, 2023		June 30, 2022		June 30, 2023		June 30, 2022
Restricted stock units	$	3.7	$	3.3	$	7.4	$	6.9
Stock options	1.0		0.9		2.1		1.9
Performance share units	2.2		2.1		4.6		4.4
Total share-based compensation expense	$	6.9	$	6.3	$	14.1	$	13.2

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

We estimated the fair value of each stock option award issued in the annual share-based compensation grant using a Black-Scholes option pricing model, modified for dividends and using the following assumptions:

	2023 Annual Grant
Risk-free interest rate	4.00	%
Expected dividend yield	2.02	%
Expected share price volatility	30.40	%
Expected term (years)	6.1